A novel hydrogen storage system of KLi3(NH2)4-4LiH with superior cycling stability

•Hydrogen storage properties of the KLi3(NH2)4-4LiH system was first examined.•The KLi3(NH2)4-4LiH system exhibits a superior cycling stability.•Mixing of potassium cations into LiNH2 can result in destabilization of LiNH2.•Dehydrogenation kinetics of the Li–N–H system is improved by mixing potassium.

In this study, we first examined the hydrogen release, uptake, and reversibility properties of the KLi3(NH2)4-4LiH system and elucidated the influence of potassium cations' substitution into LiNH2 on the hydrogen storage properties of the LiNH2-LiH composite. Our results show that mixing of the potassium cations into LiNH2 can destabilize LiNH2, therefore decreasing the hydrogen desorption temperature and enhancing hydrogen desorption rate of the LiNH2-LiH system. Notably, the KLi3(NH2)4-4LiH composite exhibits a superior cycling stability compared with the LiNH2-LiH composite prepared under the same condition.